Breaking news: Atmospheric CO2 affects global temperatures

Categories: Big picture
Published on: December 30, 2015

South Bend news-times / Garrett P Serviss / 12 September 1918

South Bend News-Times 1918Experiments show that the power of the atmosphere to trap heat is largely due to the water vapor it contains. It is also due, to some extent, to the carbon dioxide gas that is one of its minor constituents. Carbon dioxide is a remarkable heat retainer, but there is only a very small quantity of it in the air compared with the vast bulk of the atmosphere. It only amounts to about 3-100ths of 1 percent. But there is this significant fact about it, viz., that its amount is variable, to a slight degree at the present time, while there is evidence from past geological history that it was once vastly more abundant than it is now.

Now, how much carbon dioxide must the air gain in order that a perceptable effect on the temperature may be produced? Arrhenius answers that if all the carbon dioxide now in the air were removed the average temperature would fall nearly 38 degrees Fahrenheit. On the other hand, if the present amount were doubled the temperature the temperature would rise more than 7 degrees, and if it were quadrupled the rise would amount to nearly 14 1/2 degrees.